Driver assistance systems such as anti-lock braking systems (ABS) or anti-slip regulation systems (ASR) are known, via which an intervention may be performed in the vehicle to influence the driving dynamics, independent of the driver. In this case, braking or drive torques at one or more wheels of a vehicle are set to a predefined setpoint value. Precise regulation usually requires exact knowledge of a reference velocity of the vehicle, in order to be able to determine the current actual slip at the vehicle wheels. Ascertaining the reference velocity with high precision is relatively complicated, however; furthermore, determining the reference velocity during a braking process in which the anti-lock braking system is activated, or in the case of an anti-slip regulation system, in particular in vehicles with all-wheel drive, is relatively error-prone. Furthermore, determining the desired setpoint slip on various undersurfaces is a relatively complex process.